1. Field of the Invention
This invention relates generally to a method of making groups III-V single crystal semiconductors, and more particularly to a method of making a single crystal intermetallic compound by means of vapor diffusion of a metalloid into a melt of a metal using a crucible.
2. Description of the Prior Art
In U.S. Pat. No. 3,615,203 issued Oct. 26, 1972, the assignee of which is same as that of this application, there was disclosed a method of making a single crystal intermetallic compound. With this method, it requires no high temperature and high pressure so that a single crystal intermetallic compound superior in characteristic and uniform in diameter can be manufactured with a simple construction of device.
According to this method, however, there is a likelihood that a plurality of single crystals are made instead of one single crystal. In case the ingot of an intermetallic compound so manufactured is sliced to provide a wafer and a plurality of light emitting diodes are provided from the wafer, there may not be a problem. However, the plurality of light emitting diodes tend to vary in their characteristics and, especially, in the case where a monolithic alpha numeric character diplay device is formed, it is necessary that one single crystal is used therefor.
In U.S. Pat. No. 3,366,454 issued Jan. 30, 1968, a method is described for allegedly forming a single crystal in a crucible which is caused to move during the formation of the crystal. Here as in U.S. Pat. No. 3,615,205 the extent of the melt beyond the crystal-melt interface varies during the process and the formation of a single crystal only is not assured.